Q&A - P3 Math

[Muffins]

no problem!

[launt]

yeonee:

Hi, I have one question:-


John had 4 times as much money as Jessie. After John received$240 and Jessie received $180, John now has twice as much money as Jessie. How much did they have altogether at first?

Hi, I'm new here, just joined this forum. Let me try to help...
4units + 240 = 2( 1unit + 180)
4units + 240 = 2units + 360
2units = 120
1unit = 60

at first there were 5 units (john 4 + jessie 1)
5 units = 5 x 60 = $300

[shurley197323]

Hi, Jennifer ,Tianzhu. Can I know why must add 2x 150ml.

150ml transfer from the jug to the Kettle ,isn’t it 420ml + 150ml only?
I can’t explain clearly to my child. Please help…

[tianzhu]

Hi shurley197323


Please go to pg 47 and take another look at the MD.

150ml of water is transferred from the the jug to the kettle as shown by the arrow.

After transferring 150ml, one unit of water is left in the jug. Now compare the middle MD with the one at the bottom, it’s clear to see that 3units=150+420+150

Best wishes

[SPI]

Please help.


The cost of 1 chair and 2 similar table is $345.
The cost of 3 such chairs and 1 table is $335
(a) find the cost of 1 table
(b) Find the cost of 6 chairs

Thanks

[Dharma]

SPI:

Please help.


The cost of 1 chair and 2 similar table is $345.
The cost of 3 such chairs and 1 table is $335
(a) find the cost of 1 table
(b) Find the cost of 6 chairs

Thanks

6C + 2T = $670 ..........( 1 )
1C + 2T = $345 ..........( 2 )

( 1 ) - ( 2 )

5C = $325
1C = $65

Cost of 1 table = $335 - ($65 x 3) =$140
Cost of 6 chairs = $670 - ( $140 x 2 ) = $390

[femi]

tianzhu:

[quote])Aminah and Shanthinee had 128 bookmarks altogether.Aminah gave 1/4of her bookmarks to Geraldine. Shanthinee have the same number of bookmarks left. How many bookmarks had shanthinee have at first?

Hi

Are the bookmarks given to Geraldine or Shanthinee?

Please confirm if the numbers are 128 and 1/4.

Best wishes[/quote]sorry, after the Aminah gave 1/4 of her bookmarks to Geraldine,Shanthinee gave 37 of her bookmarks to geraldine.now , ....... ....... ..... .....

[imacsg]

Can someone tell me why a eight equal sides octogen cannot be tessellated?

Thanks

[iFruit]

imacsg:

Can someone tell me why a eight equal sides octogen cannot be tessellated?

Thanks

In a tessellation, the objects around a vertex must fit exactly without overlap. That means the interior angles of all the polygons meeting at a vertex must equal to 360.

For example,
In an equilateral triangle, corners of 6x triangles make 360 degrees at the vertex(6 x60)

for square, it's the corners of four squares that make a vertex (4x90)

For an octagon, the interior angle is 135 degrees. 3 x 135 = 405 and 2x 135 = 270. So, a tessellation can't be formed.

PS: An interesting formula to remember: Interior angle of a regular polygon = 180x(n-2)/n where n= number of sides.

HTH

[femi]

tianzhu:

[quote]2)Mrs Raja gave 17 boys and girls a total of 105 clips. Each boy was given 5 clips and each girl was given 7 clips.If all the girls were to give all their clips to the boys, how many more clips would each boy get?

Hi
Hope this helps.

You may use a heuristics known as Making a Supposition or Assuming Method.

Suppose all the 17 pupils are girls.

17*7 = 119
119 – 105 = 14 (fewer clips)

Each boy has 2 fewer clips.
Number of boys = 14/2 = 7

Number of girls = 10
Number of clips held by girls = 7*10 = 70

Hence each boy will get 70/7 = 10 clips (more)

Best wishes[/quote]

thanks for your help :lol: :celebrate: :love: :?: :idea: